Hot water dispenser with flow control

ABSTRACT

A hot water dispensing system includes a water tank having a heat source for heating water in the tank. The tank has a cold water inlet and a hot water outlet, and an expansion chamber is connected to the water tank. A faucet is connected to the hot water outlet of the tank. The faucet has an actuator for selectively dispensing hot water from the faucet as desired by a user. An aspirator is situated between the expansion chamber and the water tank, with an inlet coupled to the cold water inlet, an outlet communicating with the water tank and a vent opening in fluid communication with the expansion chamber. A flow control device is in fluid communication with the cold water inlet. The flow control device may be received in a pocket defined in the aspirator.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No. 60/594,241, filed on Mar. 22, 2005, which is incorporated by reference.

BACKGROUND

Liquid dispensers that mount to sinks are common. For example, such dispensers may be used to dispense filtered drinking water and/or instant hot water. Typically, these dispensers consist of two main parts, a faucet that would be situated above a sink for dispensing the liquid as desired, and another unit for mounting below the sink so it is out of view of the user and does not occupy counter space. For example, in a drinking water system the under-sink unit would include a filter or other water treatment unit connected to the faucet. For an instant hot water dispenser, the under-sink unit would have a water heater and a tank for holding hot water connected to the faucet.

With many known hot water dispensers, the tank is divided into two chambers, a main chamber in which water is heated electrically and an expansion chamber that is contiguous with the main chamber and into which water being heated in the main chamber is allowed to expand. The tank is vented to the atmosphere to preclude build up of pressure in the tank which is necessary because the tank usually has a thin wall which may even be a plastic material instead of metal.

Every time hot water is drawn from the tank, due to opening of the faucet, it is necessary to withdraw the hot water from the expansion chamber of the tank to provide for expansion of the replenishment cold water that is supplied to the main tank chamber from the building water system. Cold supply water is fed into the tank and hot water is drawn out of the expansion chamber concurrently with opening of the faucet using a venturi aspirator. When the faucet is opened it does not control dispensing of the hot water directly but, instead, it supplies cold water at the bottom of the tank which forces hot water out at the top of the tank through the faucet under moderate pressure.

The flow rate is determined by the fixed small diameter of the aspirator. The diameter needs to be large enough to allow sufficient flow at low household pressures. This same diameter results in a much faster flow at high household water pressures. Some manufacturers dampen the high flow using expensive screens and devices in the spout end piece. These devices add cost and require maintenance. With a dispenser that provides both hot and cold water, an inline flow control device on the cold water inlet line would limit the output flow for both the cold and hot water.

The teachings of the present disclosure address shortcomings associated with the prior art.

SUMMARY

In accordance with certain teachings of the present disclosure, a hot water dispensing system includes a water tank having a heat source for heating water in the tank. The tank has a cold water inlet and a hot water outlet, and an expansion chamber is connected to the water tank. A faucet is connected to the hot water outlet of the tank. The faucet has an actuator for selectively dispensing hot water from the faucet as desired by a user. An aspirator is situated between the expansion chamber and the water tank, with an inlet coupled to the cold water inlet, an outlet communicating with the water tank and a vent opening in fluid communication with the expansion chamber. A flow control device is in fluid communication with the cold water inlet. The flow control device may be received in a pocket defined in the aspirator.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings in which:

FIG. 1 illustrates a water dispensing system in accordance with teachings of the present disclosure.

FIG. 2 schematically illustrates additional aspects of the dispensing system shown in FIG. 1.

FIG. 3 is a perspective view of an aspirator for the water dispensing system shown in FIGS. 1 and 2.

FIG. 4 is a side view of the aspirator shown in FIG. 3.

FIG. 5 is a sectional view of the aspirator shown in FIGS. 3 and 4.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

DETAILED DESCRIPTION

Illustrative embodiments of the invention are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.

FIGS. 1 and 2 generally illustrate portions of a typical water dispensing system 100. The dispensing system 100 includes a faucet 110 that would be situated above a sink for dispensing the liquid as desired, and an under-sink unit 112 for mounting below the sink so it is out of view of the user and does not occupy counter space.

The faucet 110 of the illustrated dispenser includes an arched spout 114 to allow ample access to the dispenser. The illustrated system 100 dispenses both hot and cold water; thus, two actuators, or dispenser levers 116, 117 are provided that may be actuated to dispense the desired hot or cold liquid, respectively. In some units, additional dispenser levers may be provided for dispensing different liquids via the spout 114.

The under sink unit 112 includes a water heating unit, which is shown in further detail in FIG. 2. With dispensers that provide both hot and cold water as described above, a water chiller or water filter, for example, could also be included in the under sink unit 112. A tank 120 for heating water is situated inside the unit 112, with a heating element 122 positioned inside the tank 120. The heating element 122 is connected to a thermostat 124 that typically maintains the water temperature at around 190° F. Water supply lines 132 are connected to the faucet assembly 110 to provide cold water to be dispensed and supply the heating unit 112 via an inlet tube 134. When the hot water dispensing lever 116 is activated, unheated supply water flows through the supply line 132, through the faucet 110 and then into the tank 120 via the inlet tube 134. Hot water is delivered to the spout 114 through an outlet tube 136.

The tank 120 is connected to an expansion chamber 130 into which supply water that is heated in the tank 120 can expand. The expansion chamber 130 is vented to the atmosphere by way of a vent tube 140. When hot water is drawn from the tank 120 by activating the dispensing lever 116, it is necessary to withdraw the hot water from the expansion chamber 130 to provide for expansion of the replenishment cold water that is supplied to the tank 120. When the dispensing lever 116 is activated it does not directly control dispensing of hot water; rather, it supplies cold water at the bottom of the tank 120 to thereby force hot water out at the top of the tank 120 using an aspirator 142.

The aspirator 142 is shown in further detail in FIGS. 3-5. As shown in the sectional view of FIG. 5, a flow control disc 150 is received in a pocket 152 defined by the body of the aspirator 142. The pocket 152 is accessible via a threaded drain port 144. In certain embodiments, a 0.5 GPM flow control disc having a 0.062 inch diameter opening is suitable. This small diameter opening would be difficult to manufacture into the aspirator 142 itself. The flow control disc 150 is made of a flexible material, such as rubber. Using the flow control disc 150 for the small diameter of the aspirator eliminates the need to have tightly controlled processes that would be required to build this into the aspirator 142. A suitable disc 150 has a thickness of 0.125 inches, which provides satisfactory laminar flow performance. With the control disc 150 integrated into the aspirator 142, the flow is not reduced on the cold water side of the system 100 where a higher flow is desired. The flow control disc 150 further provides a generally constant flow rate at varying pressures.

Cold supply water flows into the aspirator 142 through an inlet opening 146 and through the flow control disc 150. The small inside diameter of the flow control disc 150 creates a venturi, restricting the flow through the aspirator 142. The restriction causes an increase of flow velocity, which is accompanied by reduced pressure of the water relative to the pressure of the hot water in the expansion chamber 130. Consequently, hot water from the expansion chamber 130 is drawn in through a vent hole 148 downstream of the flow control disc 150 and is discharged back into the tank 120. The incoming stream of mixed hot and cold water forces hot water out of the tank 120 and up the outlet tube 136 to be discharged from the faucet spout 114. When hot water is not being dispensed through the faucet 110, water is heated in the tank 120, and the heated water expands from the tank 120, up the aspirator 142 and through the vent hole 148 into the expansion chamber 130.

In other embodiments, the flow control disc 150 is situated in positions other than the aspirator 142. For instance, embodiments are contemplated wherein the flow control disc is at a locations on the hot water side of a hot and cold water dispensing system upstream of the aspirator 142 to control the flow rate of water entering the tank 120 and hence, the hot water exiting the faucet. In such embodiments, a venturi may be machined into the aspirator 142 to create the suction for drawing water from the expansion chamber 130 into the tank 120.

The particular embodiments disclosed above are illustrative only, as the invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the invention. 

1. A water dispensing system, comprising: a water tank having a heat source for heating water in the tank, the tank having a cold water inlet and a hot water outlet; an expansion chamber connected to the water tank; a faucet connected to the hot water outlet of the tank, the faucet having an actuator for selectively dispensing hot water from the faucet; an aspirator situated between the expansion chamber and the water tank, the aspirator having an inlet coupled to the cold water inlet, an outlet communicating with the water tank and a vent opening in fluid communication with the expansion chamber; and a flow control device in fluid communication with the cold water inlet.
 2. The water dispensing system of claim 1, wherein the aspirator defines a pocket that receives the flow control device.
 3. The water dispensing system of claim 1, wherein the flow control device defines an opening of about 0.062 inches.
 4. The water dispensing system of claim 1, wherein the flow control device is made of rubber.
 5. The water dispensing system of claim 1, wherein the flow control device defines a thickness of about 0.125 inches.
 6. The water dispensing system of claim 1, wherein the faucet includes a cold water inlet, and wherein the faucet includes a second actuator for selectively dispensing cold water from the faucet.
 7. The water dispensing system of claim 1, wherein the aspirator defines a venturi restriction.
 8. An aspirator for a water dispensing system, comprising: a body member defining a pocket; an inlet defined by the body member for receiving cold water; an outlet defined by the body member communicating with the inlet for providing the cold water received by the inlet to a water tank; a vent opening defined by the body member; and a flow control device received in the pocket.
 9. The aspirator of claim 8, wherein the flow control device defines an opening of about 0.062 inches.
 10. The aspirator of claim 8, wherein the flow control device is made of rubber.
 11. The aspirator of claim 8, wherein the flow control device defines a thickness of about 0.125 inches. 